The invention relates to the field of collator apparatus, i.e., sorting devices for sheet material as used to a large extent to produce multiple collated sets of multi-page documents which have been printed or copied.
Various collators or sorting apparatus are known in the art. Copending patent application, filed on Aug. 2, 1976, Ser. No. 710,835, and assigned to the same assignee as the present application, describes a mini-collator attached to a convenience copier, and contains a discussion of the prior art development of such apparatus. The above application, Ser. No. 710,835, is incorporated herein by reference.
The limiting factor in all prior art collators is usually the number of collator bins available, and the sheet holding capacity of each individual bin, or at least the smallest of the bins. The smaller the collator, the more important is this limitation. In the above referenced case of the mini-collator which has a very small number of bins with a limited capacity each, the operational limits, are, of course, reached much earlier than with a large collator with fifty or one hundred bins and a large sheet holding capacity. The theoretical example below shall exemplify the limitations.
In the above-referenced patent application, Ser. No. 710,835, a mini-collator is shown for the exemplary preferred embodiment as comprising ten bins with a capacity of twenty sheets each. Although this collator satisfies a very large number of customer requirements, it obviously reaches a limit as soon as documents with more than twenty original pages have to be copied and collated. When, for example, five copies of a twenty-five page document have to be produced, collation has to be made in two steps. The first step executed by the operator would be to copy the first twenty pages of the original and collate it. Then, the copies are removed from the collator. The second step would include the copying of the remaining five pages of the document, collating it, and attaching it to the already unloaded twenty page sets. On one hand, this merging of two collated half-sets requires the interaction by the operator, on the other hand, it may introduce mistakes by wrongly collating sets.
It is one object of the present invention to improve the capabilities of collators.
Another object of the invention is to enable collation of sets whose number of pages exceeds the bin's sheet holding capacity.
The further object of the invention is to provide the more efficient use of collators with limited capacities.
An additional object is to adapt a collator automatically to the collation job.
Another object is to provide a versatile and adaptive copier/collator combination.